Abstract:
A spatial filter for an optical system, such as an optical spectrometer, collects and spatially filters light using a fiber bundle having a plurality of fibers disposed therein. At an input end of the fiber bundle, the fibers are typically packed tightly together to optimize the collection efficiency. At an output end, the fibers are spread out from the fiber bundle and arranged within a two-dimensional output area according to a two-dimensional pattern corresponding to a coded aperture function. As a result, the two-dimensional pattern of the output end spatially filters the light collected by the input end. Corresponding methods are also described.
Abstract:
Systems, methods, and apparatuses of low-coherence enhanced backscattering spectroscopy are described within this application. One embodiment includes providing incident light comprising at least one spectral component having low coherence, wherein the incident light is to be illuminated on a target object in vivo. An intensity of one or more of at least one spectral component and at least one angular component of backscattering angle of backscattered light is recorded, wherein the backscattered light is to be backscattered from illumination of the incident light on the target object and wherein the backscattering angle is an angle between incident light propagation direction and backscattered light propagation direction. The intensity of the at least one spectral component and the at least one backscattering angle of backscattered light is analyzed, to obtain one or more optical markers of the backscattered light, toward evaluating said properties.
Abstract:
A spatial filter for an optical system, such as an optical spectrometer, collects and spatially filters light using a fiber bundle having a plurality of fibers disposed therein. At an input end of the fiber bundle, the fibers are typically packed tightly together to optimize the collection efficiency. At an output end, the fibers are spread out from the fiber bundle and arranged within a two-dimensional output area according to a two-dimensional pattern corresponding to a coded aperture function. As a result, the two-dimensional pattern of the output end spatially filters the light collected by the input end. Corresponding methods are also described.
Abstract:
A method and a matching system for providing high resolution spectroscopy measurements. Input light beam is spread, forming two dimensional array of beams. These beams are further intercepted by two dimensional detecting means. A corresponding electronic system interprets the power collected by each detecting element subsequently producing spectral data.
Abstract:
Systems and methods for rapid Raman spectroscopy. The speed is improved by providing light from a sample to a light-dispersive element, such as a holographic grating, in a pattern that inversely complements distortion caused by the grating. For example, if the grating imparts a curve to the spectral lines emanating from the grating, then the light is inserted into the grating in a curve in the opposite direction. Also calibration light guides able to transmit a known, or standard, light to the detection or spectroscopy system. The calibration light guide can be useful both with traditional light transmission guides and with the light transmission guides of the present invention.
Abstract:
A reflectometer for measuring absorption of light in selected regions of the light spectrum by a diffuse reflector. The reflectometer is adapted to precisely measure absorption resulting from the constituents present in body fluids. The sample to be measured is illuminated by a focussed light source at an angle of 45.degree. to its surface. The light diffusely reflected about the normal to the sample falls on a small round bundle of optical fibers. At the opposite end of the bundle, the fibers are arranged into a narrow rectangle. This rectangle forms the entrance slit for a concave holographic diffraction grating. The grating forms images of this entrance slit spectrally separated over a flat field suitable for recording the spectrum on film or on an array of discrete detectors.
Abstract:
A high resolution fast imaging spectrograph is disclosed which provides 400 spatial channels and 100 spectral channels of information. A collimating mirror (10) and a focusing mirror (12) face a plane diffraction grating (14), which is positioned at an acute angle to the perpendicular to the optic axis. An elongated slot (16) is cut through approximately the center of the grating allowing the light source (18) to pass through the slot and onto the collimating mirror. A turning mirror (20), which is placed at the focus of the focusing mirror and adjacent to the slot, directs radiation to a camera mirror (22), which focuses a final image outside the instrument enclosure onto a detector (24). The light source to the instrument is provided by an optical fiber ribbon. The detector will commonly be a CCD or CID 2-D detector, permitting the simultaneous measurement of spectral distribution of a spatial profile. The instrument requires no power input, has no moving parts, and is completely passive with no operating controls or adjustments. Also disclosed is a commercially significant means to utilize the high spatial resolution imaging spectrograph in earth science remote imaging applications through the utilization of a reflecting telescope connected to the spectrograph by means of an optical fiber ribbon.
Abstract:
A reflectometer for measuring absorption of light in selected regions of the light spectrum by a diffuse reflector. The reflectometer is adapted to precisely measure absorption resulting from the constituents present in body fluids. The sample to be measured is illuminated by a focused light source at an angle of 45.degree. to its surface. The light diffusely reflected about the normal to the sample falls on a small round bundle of optical fibers at the opposite end of the bundle, the fibers are arranged into a narrow rectangle. This rectangle forms the entrance slit for a concave holographic diffraction grating. The grating forms images of this entrance slit spectrally separated over a flat field suitable for recording the spectrum on film or on an array of discrete detectors.
Abstract:
An fixed grating, detector-array type analyzer rapidly multiplexes multiple channels. The analyzer comprises a light source, a detector array-type spectrograph, and an optical multiplexer. The multiplexer can select from one of a plurality of channels. Further, the multiplexer can convolute light passing through it with a reference spectrum for calibration and wavelength drift compensation. Rapid multiplexing is achieved using a fiber optic slit array which "perpendicularly multiplexes" the plurality of channels.
Abstract:
A single strand of an optical fiber with a single optical core that is dimensioned at one end to resemble a blade or a head of a flat-head screwdriver. Such strand of the optical fiber is configured for optical coupling of light between such single strand and a spectrometric/spectrophotometric apparatus while employing an input slit and/or an output slit of the apparatus. A method for fabricating such single strand. A fiber optic cable containing, as an optical medium, only such single strand. A method for handling light with the use of such optical fiber and/or the optical cable.